1. Field of the Invention.
Field is that of a computer compatible character adapted for being easily read by a photoreader. A computer compatible character is a legible character composed of elements each of which elements corresponds to a respective bit of a computer word.
2. Description of Prior Art.
Whitaker, U.S. Pat. No. 4,159,471 discloses a set of computer compatible characters of which the master character is shown in FIG. 1 of the present Application. Of particular interest is the numerical subset of elements forming a master numeral and shown in the present FIG. 2. Numerals are zero to fifteen and appear in FIG. 3.
All lines of every numeral are mutually contiguous. This prevents a numeral consisting of two separated lines from being mistaken for two separate numerals.
All numerals except the six and eleven may be written without lifting the pencil from the paper.
No lines appear in either the upper right or upper left regions of the rectangular character space (CS in FIG. 2) used by the numeral. Also, the lines are relatively congested about the center. For reliable reading by a photoreader it is desirable that the lines be separated as much as possible. The character should be redesigned so that elements appear in the blank upper corners.
Barnes in a U.S. Patent discusses the square shaped computer compatible numeral of FIG. 4. Not all lines are mutually contiguous. If the numerals are handwritten in free format, then question can arise regarding a numeral in which only the right and left sides are present. The two lines could be separate numerals of one vertical line each. Elements are weighted as indicated.
A gentleman in Prague in the 1950's proposed the numeral of FIG. 5. The vertical line serves as a space holder (zero). Numeral is for use with a base-64 numbering system.
Others have suggested computer compatible numerals of various configurations. One such numeral was derived from Roman numerals. Another consisted of staggered horizontal lines. A Dr. Gabrielian of California suggested a numeral identical to that of Whitaker except that the apex angle was made 90.degree. and the numeral was tilted so that one of the sides was vertical and the second was horizontal.
None of the previous disclosures was of a numeral particularly designed to provide ease and reliability of photoreading.
A character is said to be "computer compatible" if it is composed of elements, each element having a respective bit in a computer word. If the element is present in a particular character, its respective bit is hi in the computer word. This invention provides a computer compatible character which is reliably read by a photoreader. The character consists of eight equally spaced arms (elements) extending from a center (common point). This provides a set of 255 characters. The numerals of the hexadecimal numbering system are formed by the four arms extending at angles of 45.degree. to the horizon tal. Of prime interest is reading the code column of a coding sheet and feeding the resultant data to an 8-bit computer. For each 8-bit word two hexadecimal computer compatible numerals are placed side by side in the code column. A read head containing six sensors is drawn down the column. In goes the code.